The development of receptor binding radiotracers for myocardial imaging depends on high concentration of receptor in the heart and a radioligand with a high affinity for that receptor. The binding of QNG to the msucarinic cholinergic receptor in the heart is an example of such a systems. In animals heart to blood ratios of as high as 30 are obtained using tritiated QNB. Based on these results the development of a gamma emitting derivative of QNB would allow the external detection of the change in blood flow or receptors as a function of disease. Our early attempts to synthesize 4-IQNB through direct thallation of QNB were unsuccessful. The second synthetic variant - the nitration of either benzilic acid or benzil - was similarly abortive. The only successful synthetic route to date is the one described below: 4-Aminobenzil was synthesized according to a modified method of Augl and Duffy requiring six synthetic steps. The overall yield was poor ( less than 10 percent) but the availability and inexpensiveness of the starting materials renders this approach practicable. The 4-aminobenzil was rearranged to yield 4-aminobenzilic acid which in turn was esterified to its ethyl ester. The ethyl ester of 4-aminobenzilic acid was converted to the 4-triazeno-WNB according to the procedure reported by Tewson and Welch. Due to the numerous by products the purification of 4-triazeno QNB is tedious and requires several chromatographic techniques. In addition, radiohalogenation of quinuclidinyl benzilate (QNB) was attempted by electrophilic substitution and halogen exchange reactions. Rections that lead to halogenation of activated aromatic rings did not lead to iodinated QNB. Yields of 10 percent were obtained using superacid reactions. Halogen exchange reactions also produced low yields. The maximum yield was obtained at pH 5.5 in water. QNB is not readily iodinated even though the ring is not strongly deactivated to electrophilic substitution.